As is known, in tower-type malthouses a plurality of superposed floorage areas is installed, in particular one or more upper steeping floorage areas, one or more intermediate germination floorage areas and one or more lower roasting floorage areas, there being in each one of these floorage areas a machine-arm equipped with an endless belt for the adequate spreading of the product and later collection of same, as well as stirring means; the said arm rotates on a central column and is to be supplied as much with electrical current for the previously mentioned operating elements as with water at normal pressure for humidification of the product and with water at high pressure for cleansing, as well as with compressed air also.
When dealing with tower-malthouses of considerable diameter the central column not only has the function of operating as rotation axis for the various machine-arms installed in the various floorage areas of the malthouse, but in addition must constitute a strong element for supporting the flooring units of the building with the purpose of minimizing the costs of the latter, the reason why the said column is of considerable diameter.
In such cases the said column constitutes a significant obstacle for the supply ducts of cables of the machine-arm.
In an attempt to obviate this problem area malthouses are known in which the machine-arm is fixed, the base of each floorage area being rotatory, but this solution is not economical due to the large amount of weight which it is required to move, since in the loaded condition the said rotatory base may attain and even exceed seven hundred tonnes.
The other solution, in which the base is fixed and it is the machine-arm which moves, consists in installing in the roof of each floorage area a helical track with wheeled rollers for retracting the cable, but this solution is very costly, not aesthetic and has frequent problems of blockage of the rollers due to the curvature of the guide.
Neither, from the point of view of the electrical supply, is the conventional system of brushes suitable due to the large diameter of the column, which may come to attain three meters, since the mechanics of tracks with this diameter for the brushes would be exceedingly complicated and very costly while at the same time the block would be difficult to encapsulate for suitably sealing and protecting such means of connection.